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家蚕地方品种线粒体基因组A+T丰富区的序列及分子进化分析 被引量:7
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作者 陈丽媛 赵巧玲 +5 位作者 沈兴家 张志芳 唐顺明 徐安英 张国政 郭锡杰 《蚕业科学》 CAS CSCD 北大核心 2007年第1期5-13,共9页
为了研究家蚕线粒体基因组A+T丰富区的结构和家蚕品种的进化,用PCR方法扩增了12个家蚕(Bombyx mori)地方品种线粒体基因组A+T丰富区及其侧翼序列,分离纯化后克隆到pMD18-T载体进行测序。序列分析表明,克隆片段长度约1.1kb,基... 为了研究家蚕线粒体基因组A+T丰富区的结构和家蚕品种的进化,用PCR方法扩增了12个家蚕(Bombyx mori)地方品种线粒体基因组A+T丰富区及其侧翼序列,分离纯化后克隆到pMD18-T载体进行测序。序列分析表明,克隆片段长度约1.1kb,基因排列顺序与C108线粒体相同,依次为12SrRNA基因3’端、A+T丰富区、tRNA^Met、tRNA^lle。tRNA^Gln和ND2基因5’端,在tRNA^Gln和ND2基因之间有47bp的非编码区。以日本野桑蚕(Bombyx mandarina)为外群,用Phylip软件包构建了基于12个家蚕品种线粒体基因组A+T丰富区序列的NJ进化树。结果显示,甘肃种单独聚为一群,其进化早于其它11个品种聚成的类群,说明甘肃种是供试家蚕品种中进化最早的品种。这一结果在分子水平上为黄河流域是家蚕品种的发祥地之一提供了证据,也进一步支持了家蚕品种的中国起源说。对A+T丰富区及其侧翼基因的结构分析表明,家蚕线粒体12SrRNA和ND2基因都十分保守,14个品种统计只分别发生1个和2个碱基转换;A+T丰富区中(A+T)比例高达94.9%以上,第27nt开始有1个T-串结构,长度为16~19bp不等;同时还根据3个tRNA基因的核苷酸序列推定了其二级结构。 展开更多
关键词 家蚕 线粒体DNA A+T丰富区 分子进化 起源
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中国野桑蚕mtDNA中A+T丰富区片段的克隆及序列分析 被引量:5
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作者 郑小坚 曹广力 +3 位作者 薛仁宇 陈淼 何泽 贡成良 《蚕业科学》 CAS CSCD 2004年第4期348-352,共5页
对中国野桑蚕mtDNAA +T丰富区片段进行了克隆和序列分析。在所测定的 72 0bp左右的片段中 ,A +T含量为 92 0 8% ,与不同家蚕品种的mtDNA相近 ,中国野桑蚕与家蚕之间的核苷酸序列呈高度同源性 (98%以上 ) ;但与日本野桑蚕相比 ,中国野桑... 对中国野桑蚕mtDNAA +T丰富区片段进行了克隆和序列分析。在所测定的 72 0bp左右的片段中 ,A +T含量为 92 0 8% ,与不同家蚕品种的mtDNA相近 ,中国野桑蚕与家蚕之间的核苷酸序列呈高度同源性 (98%以上 ) ;但与日本野桑蚕相比 ,中国野桑蚕mtDNA的A +T丰富区片段 ,缺少 2个 12 6bp的重复单位 ,A +T含量低 0 9% ,核苷酸序列同源性也较低 (72 % )。该片段与中系家蚕mtDNA比较 ,有 15个变异位点。对mtDNAA +T丰富区的中国野桑蚕和日本野桑蚕及中系、日系和韩国的 4个家蚕品种进行聚类分析表明 ,日本野桑蚕有可能由中国野桑蚕分化而来。 展开更多
关键词 野桑蚕 MTDNA A+T丰富区 序列分析
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大蚕蛾科绢丝昆虫线粒体基因组A+T丰富区序列及其系统发育研究 被引量:4
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作者 沈兴家 陈丽媛 +4 位作者 唐顺明 孙孝龙 赵巧玲 朱晨 郭锡杰 《江苏科技大学学报(自然科学版)》 CAS 北大核心 2008年第3期66-71,共6页
为了研究大蚕蛾科绢丝昆虫的进化关系,分别从蓖麻蚕、樗蚕和柳蚕的蛹中提取线粒体DNA,用PCR方法扩增线粒体A+T丰富区及侧翼序列,克隆到pMD18-T载体,进行序列测定.序列分析表明,克隆片段的基因依次为12SrRNA基因3′端、A+T丰富区、tRNAMe... 为了研究大蚕蛾科绢丝昆虫的进化关系,分别从蓖麻蚕、樗蚕和柳蚕的蛹中提取线粒体DNA,用PCR方法扩增线粒体A+T丰富区及侧翼序列,克隆到pMD18-T载体,进行序列测定.序列分析表明,克隆片段的基因依次为12SrRNA基因3′端、A+T丰富区、tRNAMet、tRNAIle、tRNAGln和ND2基因5′端,与家蚕和野桑蚕mtDNA排列顺序相同;在tR-NAGln和ND2基因之间有一段非编码区.根据柳蚕3个tRNA基因的核苷酸序列推定了其二级结构.基于5种大蚕蛾科绢丝昆虫和家蚕mtDNA A+T丰富区序列的系统发育树显示,柳蚕与蓖麻蚕、樗蚕的亲缘关系较近,与柞蚕的亲缘关系较远,而与家蚕的亲缘关系更远.本研究结果有助于阐明大蚕蛾科绢丝昆虫以及家蚕的起源和进化. 展开更多
关键词 大蚕蛾科 非家蚕 线粒体DNA A+T丰富区 系统发育树
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三门峡风资源分析与利用
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作者 戴翠贤 范秀平 +2 位作者 王君 贾斯 方红娟 《能源与环保》 2024年第1期193-198,共6页
为充分挖掘利用三门峡风资源,利用三门峡地区站点风资料,采用ArcGIS、指数律、对数律等方法进行计算分析,结果表明,三门峡地区沿黄一带为风资源密集区,渑池、灵宝为资源丰富区,陕州区为较丰富区。根据风资源空间分布特征,调研风资源开... 为充分挖掘利用三门峡风资源,利用三门峡地区站点风资料,采用ArcGIS、指数律、对数律等方法进行计算分析,结果表明,三门峡地区沿黄一带为风资源密集区,渑池、灵宝为资源丰富区,陕州区为较丰富区。根据风资源空间分布特征,调研风资源开发利用情况,渑池、灵宝、陕州区建立风力发电场最多,渑池、陕州风资源充分开发利用。为进一步精确评估风资源开发潜力,根据风随高度变化特征,计算分析风资源潜力开发利用区,为三门峡风电场二期开发、建立风电场提供科学的依据。 展开更多
关键词 风资源 分布特征 风电场 资源丰富区 资源利用
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陶城铺灌区地下水资源合理开发和探析 被引量:1
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作者 侯玉霞 任国勇 +1 位作者 雷传起 盖志新 《地下水》 2011年第2期48-48,92,共2页
通过对陶城铺灌区地下水资源的分布、储量以及地下水含水层埋藏特点、水力性质、地质时代、水质状况进行分析,根据不同地区不同情况进行合理开发利用。
关键词 含水层 丰富区 贫乏 开采
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构建无背景的选择性感染噬菌体
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作者 陈颖 李海 吴文言 《免疫学杂志》 CAS CSCD 北大核心 2006年第5期484-486,共3页
目的构建一个选择性感染噬菌体(selectively infective phage,SIP)载体。方法删去M13KO7gIII基因的第2个甘氨酸丰富区,并在此位置插入3个内切酶识别位点,用于外源基因的插入,构建成重组噬菌体基因组BP-M13KO7。将重组噬菌体BP-M13KO7的... 目的构建一个选择性感染噬菌体(selectively infective phage,SIP)载体。方法删去M13KO7gIII基因的第2个甘氨酸丰富区,并在此位置插入3个内切酶识别位点,用于外源基因的插入,构建成重组噬菌体基因组BP-M13KO7。将重组噬菌体BP-M13KO7的培养液上清液感染XL1-Blue,检测其感染背景。结果重组噬菌体BP-M13KO7培养液上清液不具有感染性,完全消除了背景。结论通过将M13KO7gIII基因的第2个甘氨酸丰富区置换成3个内切酶识别位点,构建成的重组噬菌体无感染性背景。 展开更多
关键词 选择性感染噬菌体 M13KO7 甘氨酸丰富区
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阴道彩超在早期异位妊娠中的应用 被引量:1
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作者 吴菲 《中国卫生产业》 2012年第34期171-171,共1页
目的探讨阴道彩超在早期异位妊娠中所起到的作用,并依据可靠地临床资料来进行证实。方法选取2010年1—12月间已经使用保守治疗和手术病例方法被证实有异位妊娠的患者共60例,这些患者运用附件区包块二维和彩色图像的方法进行回顾分析。... 目的探讨阴道彩超在早期异位妊娠中所起到的作用,并依据可靠地临床资料来进行证实。方法选取2010年1—12月间已经使用保守治疗和手术病例方法被证实有异位妊娠的患者共60例,这些患者运用附件区包块二维和彩色图像的方法进行回顾分析。结果通过彩超检查得出,有6例存在附件区孕囊,其四周存在彩环状或者是局灶性血流丰富区;有54例是附件区包块,包块处探及局灶性血流丰富区的有50例;55例患者的局灶血流丰富区探及低阻力动脉血流频谱,探及盆腔无回声区的为34例。结论通过本文探讨研究发现,对于能够早期诊断异位妊娠有价值的检测方法就是引导彩超。 展开更多
关键词 阴道彩超 早期异位妊娠患者 丰富区 探讨
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Spatio-temporal variations in the siphonophore community of the northern South China Sea 被引量:2
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作者 李开枝 尹健强 +2 位作者 黄良民 练树民 张建林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期312-326,共15页
To understand how hydrological and biological factors affect near-to off-shore variations in the siphonophore community,we sampled zooplankton at 82 stations in the northern South China Sea during summer,winter,and sp... To understand how hydrological and biological factors affect near-to off-shore variations in the siphonophore community,we sampled zooplankton at 82 stations in the northern South China Sea during summer,winter,and spring.Forty-one species of siphonophore were collected by vertical trawling.The species richness of siphonophores increased from the nearshore to offshore regions in all three seasons of investigation,with maximum richness in summer and minimum richness in winter.The abundance of siphonophores was also higher in summer than in spring and winter,concentrated in the nearshore region in the warm season and scattered in the offshore region in the cold season.Four siphonophore groups were classified according to the frequency of occurrence:nearshore,near-offshore,offshore,and tropical pelagic.Among them,the nearshore group had higher abundance nearshore compared with the offshore.The tropical pelagic group had higher species number offshore than nearshore.Spatial and temporal fluctuations in taxonomic composition and abundance of siphonophores were due to the influence of the coastal upwelling and surface ocean currents of the South China Sea,driven by the East Asia monsoonal system. 展开更多
关键词 siphonophore species composition ABUNDANCE ocean current MONSOON South China Sea
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Assessing Conservation Values of Forest Communities in Nanda Devi Biosphere Reserve: Plant Diversity, Species Distribution and Endemicity 被引量:1
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作者 Balwant RAWAT Sanjay GAIROLA Ranbeer S.RAWAL 《Journal of Mountain Science》 SCIE CSCD 2015年第4期878-890,共13页
Present study has been conducted in a biodiversity rich Nanda Devi Biosphere Reserve between 2000-3800 m in two different forest physiognomy holding sites to analyze the structure and composition of the forest communi... Present study has been conducted in a biodiversity rich Nanda Devi Biosphere Reserve between 2000-3800 m in two different forest physiognomy holding sites to analyze the structure and composition of the forest communities including richness of native, non native and endemic species,and suggest conservation values at community and reserve level.A total of 60 sites were sampled and grouped in 11 and 8 communities for two representative sites Pindari-Sunderdhunga-Kafni(PSK) and Lata-Tolma-Phagti(LTP) respectively.From the sampled sites, 451 species(11.8%, 53 trees;17.71%, 80 shrubs; and 70.51%, 318 herbs) have been recorded.In general, PSK site represented 73.6% and LTP site represented only 54.9% of the total plant species recorded in the study area.Out of total species in PSK site, native species contributed 59.6%(198spp.) and 24.7% species were endemic and near endemic.In LTP site, 66.5% species were Himalayan natives and 33.5% were endemic and near endemic.The species richness ranged from 4-23 ind ha-1(tree),3-18 ind ha-1(sapling), 5-19 ind ha-1(seedling) in PSK site and 4-18 ind ha-1(tree), 4-11 ind ha-1(sapling), 4-16 ind ha-1(seedling) in LTP site.The density ranged from 260-535 ind ha-1(tree), 145-633 ind ha-1(sapling), 1450-8170 ind ha-1(seedling) in PSK site and 599-1211 ind ha-1(tree), 70-951 ind ha-1(sapling),470-1665 ind ha-1(seedling) in LTP site.Species diversity for trees ranged from 0.73-3.37, saplings,0.64-2.67, seedlings, 0.70-2.51, shrubs, 1-2.34 and herbs, 2.02-3.21 in PSK site and 0.63-1.61, saplings,0.76-1.36, seedlings, 0.35-1.79, shrubs, 0.98-2.73 and herbs, 2.48-3.61 in LTP site.These recorded values were almost comparable with the studies conducted in sub-tropical, temperate and sub-alpine regions of the west Himalaya.In some cases the values were slightly higher than the reported values.The important communities with high conservation values have been identified based on different ecological parameters and species distribution.Among all the prioritized communities, Mixed Silver firRhododendron-Maple community in PSK site and Taxus wallichana- A.pindrow mixed community in LTP site supports maximum richness and density of native and endemic species.This study calls for development of adequate strategy and action plan for the conservation and management of habitats, species,and communities under changing climate and socioeconomic scenarios, so that sustainable utilization of the species could be ensured. 展开更多
关键词 Biosphere reserve Structure Composition Native ENDANGERED Conservation
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Marine ciliate community in relation to eutrophication of coastal waters in the Yellow Sea 被引量:4
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作者 徐奎栋 CHOI Joong Ki +1 位作者 类彦立 YANG Eun Jin 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第1期118-127,共10页
We assessed the potential of marine ciliate community as an indicator to coastal water quality using water samples collected from four stations in thc Yellow Sea in the summer 2000. The four stations were characterize... We assessed the potential of marine ciliate community as an indicator to coastal water quality using water samples collected from four stations in thc Yellow Sea in the summer 2000. The four stations were characterized by different levels of pollution. The ciliate communities consisted primarily of tintinnids and aloricate ciliates that were 〈30 um. A total of 78 species were classified: 55 species at Station 2, 51 species each at Stations l and 4, and 47 species at Station 3. The mean number of species at each site was 29.2±2.0 (Station 1), 28.5±2.9 (Station 2), 27.8±1.7 (Station 3), and 24.5±2.3 (Station 4). The abundance was highly variable: 19 331±11 187 ind./L at Station 1, 7 960±5 639 ind./L at Station 2, 29 015±12 999 ind./L at Station 3, and 8 190±4 658 ind./L at Station 4. Our results suggest that neither the simple chemical analysis (e.g. chemical oxygen demand, dissolved inorganic nitrogen, and phosphate) nor the eutrophication/pollution index adequately described the water quality at the four stations. The same was true of the number of species and their abundance, both of which had no correlation with the chemical indices. In contrast, Margalef's diversity index values (3.12 at Station 2, 2.89 at Station 1, and 2.64 at Stations 3 and 4) generally discriminated the water quality status of the four stations. The difference in water quality among the stations was strongly supported by the pattern of species richness (i.e. the total number of species) of ciliates at each station. Our evaluation was consistent with the results of long-term water quality monitoring at the four stations. With increasing eutrophication, we observed also a compositional and functional shift in the ciliate assemblages from algivorous oligotrich/choreotrich to nonselective-omnivorous gymnostomatids to bacterivorous-detrivorous scuticociliatids. Thus, eiliates may be used to indicate the coastal water quality status of a given site. 展开更多
关键词 BIOMONITORING chemical evaluation CILIATES community structure EUTROPHICATION marine pollution
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Research on Countermeasures and Development Status of Red Tourism in Shandong
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作者 Liu Hongchen Zhang Lijie 《International Journal of Technology Management》 2013年第8期107-110,共4页
As a new tourism pattern, red tourism develops rapidly in China. In Shandong, not only the red cultural heritage is rich, but also the red tourism resources are rich, but the development is not very successful now. Th... As a new tourism pattern, red tourism develops rapidly in China. In Shandong, not only the red cultural heritage is rich, but also the red tourism resources are rich, but the development is not very successful now. The paper aims at surveying the status of Shandong red tourism, and analyzes the evaluation of tourists on red tourist attractions by the way of market research. The research indicates that red tourism has the problems including improper publicity, single development model and imperfect infrastructures, for which the paper proposes the suggestions such as multi-channel publicity and multi-mode development. The research results of the paper not only provides scientific basis for developing red tourism in Shandong, but also provides reference for practical management on red tourism. 展开更多
关键词 SHANDONG red tourism development status market research SPSS analysis COUNTERMEASURES
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Species-area relationship within and across functional groups at alpine grasslands on the northern Tibetan Plateau,China 被引量:1
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作者 ZHOU Nan WU Jian-shuang +2 位作者 SHEN Zhen-xi ZHANG Xian-zhou YANG Peng-wan 《Journal of Mountain Science》 SCIE CSCD 2016年第2期265-275,共11页
The species-area relationship (SAR) is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for differ... The species-area relationship (SAR) is one of the most fundamental concepts in community ecology and is helpful for biodiversity conservation. However, few studies have systematically addressed this topic for different alpine grassland types on the Tibetan Plateau, China. We explored whether the plant composition of different functional groups affects the manner in which species richness inereases with increasing area at scales ≤ 1.0 m^2. We also compared species richness (S) within and across forbs, legumes, sedges and grasses, with sampling subplot area (A) increasing from 0.0625 m^2 to 1.0 m^2 between alpine meadow and steppe communities. We applied a logarithmic function (S = b0 + b1 ln A) to determine the slope and intercept of SAR curves within and across functional groups. The results showed that the logarithmic relationship holds true between species richness and sampling area at these small scales. Both the intercept and slope of the logarithmic forbs-area curves are significantly higher than those for the three other functional groups (P 〈 0.05). Forb accounts for about 91.9 % of the variation in the intercept and 75.0% of the variation in the slope of the SAR curve when all functional groups' data were pooled together. Our results indicated that the different SAR patterns should be linked with species dispersal capabilities, environmental filtering, and life form composition within alpine grassland communities. Further studies on the relationship between species diversity and ecosystem functions should specify the differential responses of different functional groups to variations in climate and anthropogenic disturbances. 展开更多
关键词 Changtang Nature Reserve Complementary response Plant functional groups Plant life forms Species coexistence
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Diversity, Endemism and Conservation of Ferns(Polypodiales) in the Mexican Mountain Component 被引量:2
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作者 SANGINéS-FRANCO Celia LUNA-VEGA Isolda +3 位作者 CONTRERAS-MEDINA Raúl ESPINOSA David TEJERO-DíEZ José Daniel RIVAS Gerardo 《Journal of Mountain Science》 SCIE CSCD 2015年第4期891-904,共14页
We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices an... We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity analyses.Distributional data were obtained from several herbaria and specialized literature.Five grid-cells appear to be important for fern species richness, as they contain 35 to 49 species.These gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and SMS.The richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of Mexico.Some important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected Areas.The beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain systems.On the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central Plateau.Ferns play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico. 展开更多
关键词 BIOGEOGRAPHY Distributional patterns Leptosporangiate ferns Mexico
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Investigation on the spatiotemporal complementarity of wind energy resources in China 被引量:12
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作者 LIU Yi XIAO LiYe1,2 +2 位作者 WANG HaiFeng LIN LiangZhen DAI ShaoTao 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第3期725-734,共10页
Wind power resources are abundant in China,especially in northern China and eastern coastal areas of China.Nevertheless,wind energy has intermittent and unstable characteristics,which leads to random power output and ... Wind power resources are abundant in China,especially in northern China and eastern coastal areas of China.Nevertheless,wind energy has intermittent and unstable characteristics,which leads to random power output and limits the large-scale utilization of wind energy resources.It has been shown that geographically dispersed wind plants have obvious spatiotemporal offsetting effect.Power output from each individual site exhibits the power ups and downs.However,when we simulate power lines connecting sites over a certain region,the output from them changes slowly and rarely reaches either very low or full power.Hence using the spatiotemporal complementarity of wind resources effectively is highly beneficial to the smoothing of power supply.This paper investigates the spatiotemporal complementarity of wind resources in China based on the relevant data of wind energy resources,which are offered by China Meteorological Administration(CMA). 展开更多
关键词 wind energy complementarity renewable energy
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Partitioning the effects of environmental and spatial heterogeneity on distribution of plant diversity in the Yellow River Estuary 被引量:2
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作者 YUAN Xiu MA KeMing WANG De 《Science China(Life Sciences)》 SCIE CAS 2012年第6期542-550,共9页
For successful conservation and restoration of biodiversity,it is important to understand how diversity is regulated.In the ecological research community,a current topic of interest is how much of the variation in pla... For successful conservation and restoration of biodiversity,it is important to understand how diversity is regulated.In the ecological research community,a current topic of interest is how much of the variation in plant species richness and composition is explained by environmental variation(niche-based model),relative to spatial processes(neutral theory).The Yellow River Estuary(YRE) is a newly formed and fragile wetland ecosystem influenced by both the Yellow River and Bohai Bay.Here,we applied variance partitioning techniques to assess the relative effects of spatial and environmental variables on species richness and composition in the YRE.We also conducted a species indicator analysis to identify characteristic species for three subestuaries within the YRE.Partial redundancy analysis showed that the variations in species richness and composition were explained by both environmental and spatial factors.The majority of explained variation in species richness and composition was attributable to local environmental factors.Among the environmental variables,soil salinity made the greatest contribution to species abundance and composition.Soil salinity was the most important factor in the Diaokou subestuary,while soil moisture was the most important factor influencing species richness in the Qingshui and Chahe subestuaries.The combined effects of soil salinity and moisture determined species richness and composition in the wetlands.These results increase our understanding of the organization and assembly of estuarine plant communities. 展开更多
关键词 ENVIRONMENT spatial variation species composition species richness variation partitioning
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